J/A+A/457/721 IRON Project. LXII. Fe XVIII transitions (Nahar, 2006)
Atomic data from the Iron Project.
LXII. Allowed and forbidden transitions in Fe XVIII in relativistic
Breit-Pauli approximation.
Nahar S.N.
<Astron. Astrophys. 457, 721 (2006)>
=2006A&A...457..721N 2006A&A...457..721N
ADC_Keywords: Atomic physics
Keywords: atomic processes - atomic data - line: formation - X-rays: general -
ultraviolet: general - infrared: general
Abstract:
An extensive set of oscillator strengths (f), line strengths (S) and
radiative decay rates (A) for the allowed and forbidden transitions in
Fe XVIII is presented. The results include 1174 fine structure levels
of total angular momenta J=1/2-17/2 of even and odd parities with
2≤n≤10, 0≤l≤9, orbital angular momenta, 0≤L≤11, and spin
multiplicities 2, 4. These yield about 171500 transitions. The
allowed electric dipole (E1) transitions, 141 869 in total, are
obtained in the close coupling approximation using the relativistic
Breit-Pauli R-matrix (BPRM) method. The forbidden electric quadrupole
(E2), octupole (E3), and magnetic dipole (M1), quadrupole (M2)
transitions, 29 682 in total, are obtained from configuration
interaction Breit-Pauli atomic structure calculations using the code
SUPERSTRUCTURE. The close coupling wavefunction expansion for Fe XVIII
includes 10 levels of configurations 2s2 2p4, 2s2p5, and 2p6
in the BRPM calculations. All fine structure levels have been
identified spectroscopically.
Erratum:
A bug was detected and corrected in early 2007 in one of the stages
called RECUPD (Storey, Berrington, Werner, 2007, private Iron Project
communications) of the Breit-Pauli R-matrix (BPRM) codes of the Iron
Project. It was related to the the phase factor of dipole matrix
elements of the Iron Project (Berrington et al., 1995, Comput. Phys.
Commun. 92, 290) and affected certain transition probabilities. The
new results on energies and transition probabilities for Fe XX (Nahar,
2004, J/A+A/413/779) and Fe XVIII (Nahar, 2006, J/A+A/457/721, this
paper) using the corrected code are replacing the earlier results at
CDS.
It should be noted that stage RECUPD in BPRM codes does not exist in
the LS coupling R-matrix code from the Opacity Project (Berrington et
al., 1987, J. Phys. B 20, 6379) and hence does not affect the
non-relativistic results.
Results for other ions, obtained using BPRM codes, did not indicate
the bug effect when compared with existing results. However, I am
repeating the calculations for these ions and will replace the earlier
results.
The E1 transition probabilities for Fe XX have been recomputed. The
new files are:
table3a, table3b -> fine structure energy levels of Fe XVIII
table4a, table4b -> complete table of E1 fine structure transitions in
Fe XVIII
table5 -> table of fine structure transitions in Fe XVIII using
observed energies
In paper LIV (Fe XX), J/A+A/413/779, files were also corrected.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3a.txt 92 1582 *Fine structure energy levels of Fe XVIII as
sets of LS term components.
table3b.dat 74 1174 Fine structure energies in sets of various
Jπ symmetries of Fe XVIII.
table4a.dat 79 1174 Energy level
set.dat 26 25 Set of initial and final g, P and N values
for table4b.dat
table4b.dat 79 141869 f-, S and A-values for allowed E1 transitions
in Fe XVIII.
table5.dat 80 93 *Oscillator strengths f, S, A-values for
allowed E1 fine structure transitions with
the observed energy levels only
table7.dat 80 243 *Fine structure levels of Fe XVIII and their
relative energies for which forbidden
transitions have been obtained.
table8a.dat 91 4782 *Forbidden octupole E3 and quadrupole M2
transitions in Breit-Pauli approximation
table8b.dat 91 12896 *Forbidden quadrupole E2 and dipole M1
transitions in Breit-Pauli approximation
f.allowed.fe18.user 86 145972 Original file for tables 3 and 4
f.forbid.fe18.user 92 18009 Original file for tables 7 and 8
lifetime.f 79 212 Fortran code for f.allowed.fe18.user and
f.forbid.fe18.user
--------------------------------------------------------------------------------
Note on table3a.txt: Total number of levels = 1174
C_t is the core configuration, nu is the effective quantum number.
Nlv=Number of levels expected
Nlv(c)=Number of levels obtained
Nlv=Nlv(c) -> set complete
For Equivalent electron levels:
(i) no EQN (effective qn)
(ii) no check of set completeness
First lines:
Configuration J E(Ry) EQN LS terms
Eqv electron/unidentified levels, parity: o
2s22p5 3/2 -9.98779E+01 2 P o
2s22p5 1/2 -9.89033E+01 2 P o
Nlv(c)= 2 : set complete
Eqv electron/unidentified levels, parity: e
2s22p5 1/2 -9.00863E+01 2 S e
Nlv(c)= 1 : set complete
Nlv= 3, 4Le: P ( 5 3 1 )/2
2s22p4 (3Pe) 2 3s 5/2 -4.30858E+01 2.74 4 P e
2s22p4 (3Pe) 0 3s 3/2 -4.28383E+01 2.72 4 P e
2s22p4 (3Pe) 1 3s 1/2 -4.23704E+01 2.74 4 P e
Nlv(c)= 3 : set complete
Note on table5.dat: nz = 26, No. of core electrons = 8
Number of observed levels = 47, No of transitions = 76
ERRATUM: Results for E1 transitions correspond to repeated calculations after
correcting the phase bug in Breit-Pauli R-matrix code. The bug affected
certain transitions.
Note on table7.dat: Ion: nz = 26, nelc = 9
Total Number of LS terms= 108
Number of fine structure levels = 243
Number of default fine structure levels = 243
Fine Structure energies: relativistic(BP):
level 73 = 2De(J2= 5), cnf =11 has the largest % diff=
Note on table8a.dat table8b.dat:
Table 8 of radiative decay rates in s-1 for the forbidden electric quadrupole
(AE2), electric octupole (AE3), magnetic dipole (AM1) and magnetic quadrupole
(AM3) transitions in Fe XVIII.
Number of transitions: E3 = 4782, M2 = 3378, Total E3+M2 = 8160
Total number of lines of M2/E3 transitions = 4782
Number of transitions: E2 = 12084, M1 = 9438, Total E2+M1 = 21522
Total number of transitions lines (including non-spectroscopic) = 12896
NT= total number of forbidden (E2,M1,E3,M2) transitions
= 21522 + 8160 = 29682
--------------------------------------------------------------------------------
See also:
J/A+AS/103/273 : IRON Project II IR collision strengths of C-like ions
J/A+A/283/319 : IRON Project III B-like ions
J/A+AS/108/1 : IRON Project V Collision strengths of O-like ions
J/A+A/293/953 : IRON Project VI Fe II collision strengths
J/A+A/293/967 : IRON Project VII Fe II radiative transitions
J/A+AS/109/193 : IRON Project VIII Electron excitation of Ti-like ions
J/A+AS/119/509 : IRON Project XVII Radiative transition in Fe III
J/A+AS/119/523 : IRON Project XVIII Electron impact for Fe III
J/A+AS/120/361 : IRON Project XIX Fe II radiative transitions
J/A+AS/123/159 : IRON Project XXII C and O radiative rates
J/A+AS/123/575 : IRON Project XXIII Fe XXII excitation rate coefficients
J/A+AS/126/373 : IRON Project XXVII Fe IV collision strengths
J/A+AS/131/499 : IRON Project XXIX Boron isoelectronic sequence
J/A+AS/131/153 : IRON Project XXXI Fe XII electron excitation
J/A+AS/135/347 : IRON Project XXXV Fe XXIV & Fe XXV oscillator strengths
J/A+AS/136/395 : IRON Project XXXVII Fe VI collision strengths
J/A+AS/137/165 : IRON Project XXXVIII Fe XV fine-structure transitions
J/A+AS/143/483 : IRON Project XLII Fe XXI electron impact excitation
J/A+AS/144/141 : IRON Project XLIII Fe V transition probabilities
J/A+AS/147/111 : IRON Project XLIV Fe VI trans. prob. & line ratio
J/A+AS/147/253 : IRON Project XLV Ar XIII, Fe XXI trans. probabilities
J/A+A/365/268 : IRON Project XLVII Ni III electron impact excitation
J/A+A/372/1078 : IRON Project XLIX Fe XX electron impact excitation
J/A+A/372/1083 : IRON Project L Fe XIX electron impact excitation
J/A+A/394/753 : IRON Project LI Fe IX electron impact excitation
J/A+A/408/789 : IRON Project LIII Fe XVII transition probabilities
J/A+A/413/779 : IRON Project LIV Fe XX transition probabilities
J/A+A/420/763 : IRON Project LV Ni II electron impact excitation
J/A+A/437/345 : IRON Project LIX Fe IV transition probabilities
J/A+A/448/779 : IRON Project LXI Fe IV radiative transitions
J/A+A/466/763 : IRON Project LXIII Fe19+ electron impact excitation
Byte-by-byte Description of file: table3b.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Nlv Total number of symmetry Jπ (1)
5- 10 A6 --- Jpi J value and parity (o: odd, e: even)
13- 15 I3 --- iii level index (in range 1..Nlv)
17- 22 A6 --- Ct Target configuration (2)
28- 30 A3 --- SLpit Target core level
33- 35 A3 --- Jt Target J value (2)
37- 39 A3 --- nl Principal and orbital quantum numbers of
the outer electron
42- 45 A4 --- J J value (repetition of bytes 5-8)
48- 59 E12.5 Ry Elev Energy of the level
61- 65 F5.2 --- EQN ? Effective Quantum Number (3)
68- 74 A7 --- Terms Possible LS terms of the energy level
--------------------------------------------------------------------------------
Note (1): total number of levels belonging to the specified symmetry.
Z = 26, No. of core electrons = 8, Nlv(cal) = 1174
Target levels: 10
---------------------------------------
Config SLp J E(Ry)
---------------------------------------
1 2s22p4 3Pe 2 0.00000E+00
2 2s22p4 3Pe 0 6.85000E-01
3 2s22p4 3Pe 1 8.15050E-01
4 2s22p4 1De 2 1.53869E+00
5 2s22p4 1Se 0 2.96280E+00
6 2s2p5 3Po 2 8.40990E+00
7 2s2p5 3Po 1 8.97360E+00
8 2s2p5 3Po 0 9.38623E+00
9 2s2p5 1Po 1 1.15510E+01
10 2p6 1Se 0 1.94480E+01
---------------------------------------
Number of fine structure levels:
----------------------------------------
J pi Nlv(c)
----------------------------------------
1 0 74
1 1 73
3 0 112
3 1 114
5 0 117
5 1 114
7 0 94
7 1 96
9 0 74
9 1 72
11 0 51
11 1 55
13 0 32
13 1 36
15 0 16
15 1 22
17 0 12
17 1 10
----------------------------------------
Total number of levels = 1174
Note (2): T(config SLpi Jt): T -> target (core) of the level
Note (3): No EQN is assigned for Equivalent electron levels
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4a.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 5 I4 --- i [1,1174] Level index
8- 10 F3.1 --- J J value
12 A1 --- p [eo] Parity (o: odd, e: even)
15- 17 I3 --- iii Level position index within J+p
22- 33 E12.7 Ry Eobs Energy (1)
36- 53 A18 --- conf Configuration
55- 61 A7 --- LS LS term (2)
73- 79 I7 --- jjpiiii Energy level ids (3)
--------------------------------------------------------------------------------
Note (1): nz = 26 , No. of core electrons= 8
1174 = number of energies (Ecalc are replaced by available' Eobs)
Note (2): Note that there may be more than one possible LS term for some
j-levels. Simple assumption: higher L -> lower energy
Note (3): Energy levels with ids: jjpiiii
jj=2 x total angular momentum j, p=parity, iii=level position.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: set.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Set Set number
4- 5 I2 --- gi Initial statistical weight factor
7 I1 --- Pi [0/1] Initial parity value
9- 10 I2 --- gf Final statistical weight factor
12 I1 --- Pf [0/1] Final parity value
14- 16 I3 --- Ni Initial Nlv value
18- 20 I3 --- Nf Final Nlv value
22- 26 I5 --- NN Total number of transitions in the set
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4b.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Set Set, as defined in set.dat file
5- 7 I3 --- i Initial level (index in set)
9- 11 I3 --- j Final level (index in set)
13- 22 F10.2 0.1nm wl Wavelength of the transition
24- 34 E11.6 Ry Ei Initial energy
36- 46 E11.6 Ry Ej Final energy
48- 57 E10.5 --- fL fL value
60- 68 E9.4 --- S Line strength
71- 79 E9.4 s-1 Aji Einstein Aji coefficient
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
2- 7 A6 --- Ci Initial configuration
14- 25 A12 --- Cj Final configuration
26- 28 A3 --- slpi Initial core level (G1) (G2)
30- 32 A3 --- slpj Final core level (G1) (G2)
34- 35 I2 --- gi Initial statistical weight factor
37- 38 I2 --- Ii ? Energy level index of 2Ji+1
(no value when Ci = LS)
40- 41 I2 --- gj Final statistical weight factor
43- 44 I2 --- Ij ? Energy level index of 2Jj+1
(no value when Ci = LS)
48- 53 F6.2 0.1nm Eij ? Transition energy
55- 62 E8.3 --- f Oscillator strength (f value)
64- 71 E8.3 --- S Line strength
73- 80 E8.3 s-1 A Radiative decay rate (A value)
-----------------------------------------------------------------------------
Byte-by-byte Description of file: table7.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
3- 5 I3 --- ie Fine structure energy level
8- 14 A7 --- SLp(Cf) Theoretical LS symmetry of the level and the
configuration number (G1)
17- 18 I2 --- 2J Theoretical 2J value
22- 30 F9.1 --- k*cm Theoretical k*cm value
32- 41 E10.5 Ry Eth Theoretical energy
43- 55 A13 --- Conf Configuration
60- 63 I4 --- SLP Expected SLP value
65- 74 E10.5 Ry E Expected energy (actual set to use)
78- 80 F3.1 --- df %df value
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8a.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Ni Initial number
5- 7 I3 --- Nj Final number
9- 13 A5 --- SLpi(Ci) Initial core level (G1) (G2)
15- 19 A5 --- SLpj(Cj) Final core level (G1) (G2)
21- 22 I2 --- gi Initial statistical weight factor
24- 25 I2 --- gj Final statistical weight factor
27- 35 F9.2 0.1nm wl Wavelength in vacuum
37- 45 E9.4 Ry Ei Initial energy
47- 55 E9.4 Ry Ej Final energy
57- 64 E8.3 --- SE3 E3 line strength (G3)
66- 73 E8.3 s-1 AE3 Forbidden E3 transition probability
75- 82 E8.3 --- SM2 M2 line strength (G3)
84- 91 E8.3 s-1 AM2 Forbidden M2 transition probability
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8b.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Ni Initial number
5- 7 I3 --- Nj Final number
9- 13 A5 --- SLpi(Ci) Initial core level (G1) (G2)
15- 19 A5 --- SLpj(Cj) Final core level (G1) (G2)
21- 22 I2 --- gi Initial statistical weight factor
24- 25 I2 --- gj Final statistical weight factor
27- 35 F9.2 0.1nm wl Wavelength in vacuum
37- 45 E9.4 Ry Ei Initial energy
47- 55 E9.4 Ry Ej Final energy
57- 64 E8.3 --- SE2 E2 line strength (G3)
66- 73 E8.3 s-1 AE2 Forbidden E2 transition probability
75- 82 E8.3 --- SM1 M1 line strength (G3)
84- 91 E8.3 s-1 AM1 Forbidden M1 transition probability
--------------------------------------------------------------------------------
Global notes:
Note (G1): The configuration indices (Cf, Ci or Cj) correspond to:
1 = 2s22p5
2 = 2s2p6
3 = 2s22p43s
4 = 2s22p43p
5 = 2s22p43d
6 = 2s22p44s
7 = 2s22p44p
8 = 2s22p44d
9 = 2s22p44f
10 = 2s2p53s
11 = 2s2p53p
12 = 2s2p53d
13 = 2s2p54s
14 = 2s2p54p
15 = 2s2p54d
Note (G2): T denotes the LS term, SLπ, and Ntr is the number of transitions
Note (G3): Ignore the negative signs in line strengths S
--------------------------------------------------------------------------------
Acknowledgements: Sultana Nahar, nahar(at)astronomy.ohio-state.edu
References:
1993A&A...279..298H 1993A&A...279..298H : IRON Project I Goal and methods
1994A&AS..107...29S 1994A&AS..107...29S : IRON Project IV Electron excitation of F-like ions
1995A&AS..110..209P 1995A&AS..110..209P : IRON Project IX Electron excitation of Cl-like ion
1995A&AS..111..347G 1995A&AS..111..347G : IRON Project X Si- & S-like ions IR coll. strengths
1996A&AS..115..151S 1996A&AS..115..151S : IRON Project XI Ar VI, K VII & CaVIII fine-structure
1995A&AS..114..367B 1995A&AS..114..367B : IRON Project XII V-like ions electron excitation
1996A&AS..115..551B 1996A&AS..115..551B : IRON Project XIII Ni II & Fe II electron excitation
1996A&A...309..677S 1996A&A...309..677S : IRON Project XIV Fe XIV fine-structure transition
1996A&AS..118..157K 1996A&AS..118..157K : IRON Project XV He II & Fe XXVI Electron excitation
1996A&AS..119..105B 1996A&AS..119..105B : IRON Project XVI Fe V oscillator strengths
1997A&AS..122..167B 1997A&AS..122..167B : IRON Project XX Fe I oscillator strengths
1997A&AS..122..177P 1997A&AS..122..177P : IRON Project XXI Fe I fine-structure transition
1997A&AS..126..105B 1997A&AS..126..105B : IRON Project XXIV Fe XXIV electron excitation
1998A&AS..127..545B 1998A&AS..127..545B : IRON Project XXV Fe XII electron excitation
1997A&AS..126..365B 1997A&AS..126..365B : IRON Project XXVI Fe IV oscillator strengths
1998A&AS..129..161B 1998A&AS..129..161B : IRON Project XXVIII F-like ions fine-structure trans.
1999A&AS..134..369S 1999A&AS..134..369S : IRON Project XXX P III, S IV & Cl V collision data
1998A&AS..133..245G 1998A&AS..133..245G : IRON Project XXXII Ar III effective collision strength
1999A&AS..135..159M 1999A&AS..135..159M : IRON Project XXXIII Carbon radiative rates
1999A&AS..136..385E 1999A&AS..136..385E : IRON Project XXXIV Fe XVI electron impact excitation
1999A&AS..137..175C 1999A&AS..137..175C : IRON Project XXXVI Fe XXIII electron excitation
1999A&AS..137..529B 1999A&AS..137..529B : IRON Project XXXIX Ni II oscillator strengths
2000A&AS..141..285S 2000A&AS..141..285S : IRON Project XL Fe XIV electron excitation
2000A&AS..142..313B 2000A&AS..142..313B : IRON Project XLI Fe VII electron excitation
2001A&A...365..258P 2001A&A...365..258P : IRON Project XLVI Fe X electron excitation
2003A&A...401.1177C 2003A&A...401.1177C : IRON Project LII Ni24 electron excitation
2005A&A...436.1123M 2005A&A...436.1123M : IRON Project LVII Ni IV radiative transition rates
2005A&A...433..717S 2005A&A...433..717S : IRON Project LVIII Fe XII electron impact excitation
2006A&A...446..361W 2006A&A...446..361W : IRON Project LX Fe17+ electron impact excitation
History:
* 19-Sep-2006: Original version
* 06-Nov-2008: corrected version, table3, table4, table5
(End) Patricia Vannier [CDS] 17-Jul-2006